Wireless communication for downhole tools and method

ABSTRACT

A system for setting a tool in a downhole environment includes a communicator configured to broadcast a signal; a downhole tool configured to receive the signal from the communicator and execute on an instruction conveyed by the signal, a radio wave inhibiting structure being interposed between the communicator and the downhole tool and method.

CROSS REFERENCE TO RELATED APPLICATION

The present application claims priority to U.S. Provisional PatentApplication Ser. No. 60/992,490, filed Dec. 5, 2007, the entire contentsof which are specifically incorporated herein by reference.

BACKGROUND

Many tools in the downhole industry are actuated by other tools that are“run in the hole” for just that purpose. This implies, and often is thecase, that an extra step in well production is necessary. In order toreduce the number of runs and therefore reduce costs of building andrunning a well system, the art has been provided with and still activelyseeks additional means for actuating downhole tools that do not requireseparate runs or at least can increase the functionality of eachparticular run. Moreover, many downhole tools require openings throughthe casing wall to allow actuations to occur. While this method is welltried and true, there are drawbacks to such tools having an opening inthe casing or other tubular structure to which the specific tool ismounted. Such drawbacks include but are not limited to the potential fora leak path through the opening. The art would well receive a systemthat avoids such openings.

SUMMARY

A deliverable downhole communicator including a shaped object; and acommunication medium emitter in contact with the object, the emitteremitting a signal capable of passing through a radio wave inhibitingstructure.

A system for setting a tool in a downhole environment includes acommunicator configured to broadcast a signal; a downhole toolconfigured to receive the signal from the communicator and execute on aninstruction conveyed by the signal, a radio wave inhibiting structurebeing interposed between the communicator and the downhole tool.

A method for communicating with a downhole tool includes delivering acommunicator to a position proximate a downhole tool; and emitting asignal from the communicator receivable by the downhole tool through aradio wave inhibiting structure without an opening therein for passageof radio waves.

BRIEF DESCRIPTION OF THE DRAWINGS

Referring now to the drawings wherein like elements are numbered alikein the several Figures:

FIG. 1 is a schematic cross-sectional representation of a wellboreillustrating a communicator as disclosed herein; and

FIG. 2 is a schematic representation of a packer responsive foractuation to the communicator illustrated in FIG. 1.

DETAILED DESCRIPTION

Referring to FIG. 1, a deliverable downhole communicator 10 isillustrated during its trip down a wellbore 12 to a target device 14 inthe downhole environment. The communicator 10 as illustrated is anindependent device that is capable of being pumped, dropped, lowered,etc. into the downhole environment. The communicator 10 harbors acommunication medium (signal) emitter 16 somewhere within or on thesurface of the communicator 10 that is capable of broadcasting a signalsuch as an acoustic signal, a magnetic field, a gamma wave signal, arecording (even voice), etc. The signal may be continuously broadcast,on a timer, may begin at a selected depth, may begin when contact ismade with a certain chemical, when another field is encountered, uponreceiving a certain start (or stop) signal (assuming that thecommunicator utilizes a transceiver or includes a separate receiver) andcould be configured to operate utilizing a combination of these orcombinations including at least one of the foregoing. In any event, thecommunicator utilizes a wireless signal to communicate instructions to adownhole tool while not requiring a high output as might otherwise berequired due to the distance norms associated with wireless downholecommunication systems. The communicator 10 in one embodiment willinclude an on board power source to drive the signal emitter 16. Thesource may be a battery or may be a pressure based energy source orelectrochemically based energy source. It is, of course, possible topower the communicator from the surface if indeed it is tethered in someway thereto such as on slickline or wireline, etc.

In embodiments where the power source is on board allowing thecommunicator to be completely self contained the configuration of thecommunicator may be in that of a ball, a dart, a rotary wing with agravity pendant, etc. In some instances, it may be desirable to slow thedescent of the communicator into the downhole environment. This can bedone effectively with: the rotary wing embodiment and is adjustabledepending upon the angle of the wing, a parachute attached to any of theconfigurations of the communicator 10, a selection of the density of thecommunicator 10 relative to the density of the fluid in the hole, etc.

In each case, the communicator 10 is moved or allowed to move throughthe wellbore 12 and as it does so it will communicate its instructionsto a target downhole tool. This can occur by the communicatorcontinuously emitting a signal that is recognized by a target downholetool as the communicator passes that tool. The result then is that thedownhole tool will do whatever it was programmed to do upon receivingthe signal. This could be the inflation of a packer, firing of aperforating gun, actuating of a sleeve, or any other operation desired.As noted, the mode of operation of the communicator can also beintermittent based upon any of the foregoing listed factors. In suchembodiments, the communicator will begin to emit at a selected time suchthat the downhole target tool will be able to receive the signal.

In one embodiment contemplated herein, each communicator 10 will have aspecific communication medium or frequency such that it controls onlyone downhole tool. Such a condition will ensure selective actuation ofselected downhole tools only. In other contemplated embodiments, thecommunicator will utilize a spread spectrum frequency (a minimum of twofrequencies or two communication mediums) such that a number of downholetools may be addressed in a single “run” of the communicator. In thiscondition, different frequencies or communication mediums will commenceat the same time, the target downhole tools effectively identifyingthemselves by responding to only one of the frequencies or communicationmediums while other tools will respond to other of the signals. It willbe understood in view of other teachings herein however that the spreadspectrum may not require that the different frequencies/mediums beginemitting at the same time but rather that they may begin at differenttimes upon impeti as noted above.

Further, it is contemplated that the communicator 10 may be responsiveto a response signal from one or more of the downhole tools with whichit becomes proximate, for example, to change the frequency at which itis operating to ensure that the next addressed downhole tool is actuatedonly if the first addressed downhole tool responds to the communicator'ssignal, thereby changing the frequency of the communicator's signal.

Recordation playback, as noted above, can include any type of signaldesired but the use of the recordation playback embodiment allowscommunicators to be manufactured as blanks and then set to perform thedesired task at the well site. Such recordation playback embodiments caneven utilize voice recordings for specific instructions to downholetools providing that the downhole tools are configured with voicerecognition software similar to that used for computer dictation ortelephone operator assistance.

Regardless of the specific configuration of the communicator 10, it isaxiomatic that the signal emitter 18 will require protection in thedownhole environment. Such protection can be supplied by embedding orenveloping the signal emitter within the communicator shell 20 or bymounting the emitter on the surface of the communicator shell 20 if theemitter is appropriately constructed for this location.

Referring to the shell 20 of the communicator 10, it is to beappreciated that the material of the shell 20 may be of many types ofmaterial. The material must be transmissive to the communication mediumbeing employed and be sufficiently durable to endure the downholeenvironment for long enough to accomplish its mission. Beyond theserequirements though, in some embodiments it is desirable to constructthe communicator from dissolvable material so that over a period of timelonger than its intended useful life, it will dissolve in wellborefluids thereby not being an impediment to any other downhole operations.Alternatively, the communicator may be constructed of an easilydrillable material so that regardless of the fact that it will remain inthe wellbore, any further drilling operations will be unaffected by thecommunicator.

The communicator 10 as described above is particularly useful in oneembodiment to actuate downhole tools that do not include any openingsthrough the casing wall. As will be recognized by one of ordinary skillin the art, technologies such as RFID require an opening in the casingto allow the radio waves emitted thereby to escape the metal casing andreach the tool to be actuated. Since this is a potential leak path, itis undesirable. In one embodiment of the communicator 10, acousticenergy is used and thus requires no opening in order to penetrate thecasing wall.

In one embodiment, the tool is a packer 30, see FIG. 2, and thecommunicator is a ball type communicator that is in the process of beingpumped or allowed to fall to or through proximity with the packer 30.The acoustic signal 32 is illustrated emanating from the communicator10. As the acoustic signal will pass through the casing 34, the signalhas no difficulty reaching the packer 30 and providing whateverinstructions are needed for the packer to take appropriate action.

The packer 30 in one embodiment includes its own setting forcearrangement. This may be a gas generation system that is actuated by theacoustic signal or may be an electrical setting system actuated by theacoustic signal (or other communication medium). In such case, thepacker may be set in response to the acoustic signal being receivedthereby when the communicator 10 reaches proximity with the packer 30.this is accomplished without the need for an opening and therefore theavoidance of a potential leak path.

While preferred embodiments have been shown and described, modificationsand substitutions may be made thereto without departing from the spiritand scope of the invention. Accordingly, it is to be understood that thepresent invention has been described by way of illustrations and notlimitation.

1. A deliverable downhole communicator comprising: a shaped object; anda communication medium emitter in contact with the object, the emitteremitting a signal capable of passing through a radio wave inhibitingstructure.
 2. The communicator as claimed in claim 1 wherein the mediumis acoustic energy.
 3. The communicator as claimed in claim 1 whereinthe medium is a magnetic field.
 4. The communicator as claimed in claim1 wherein the medium is gamma energy.
 5. The communicator as claimed inclaim 1 wherein the medium is a voice recording.
 6. The communicator asclaimed in claim 1 wherein the object is a ball.
 7. The communicator asclaimed in claim 1 wherein the object comprises a dissolvable materialshell.
 8. The communicator as claimed in claim 1 wherein the emitteremits the selected medium continuously.
 9. The communicator as claimedin claim 1 wherein the emitter emits the selected mediumdiscontinuously.
 10. The communicator as claimed in claim 10 wherein theemitter emits pursuant to a timer.
 11. The communicator as claimed inclaim 10 wherein the emitter emits pursuant to contact with a particularchemical.
 12. The communicator as claimed in claim 10 wherein theemitter emits pursuant to being exposed to a selected pressure.
 13. Thecommunicator as claimed in claim 1 wherein the emitter emits at leasttwo frequencies or at least two mediums.
 14. The communicator as claimedin claim 1 wherein the communicator is untethered to a remote locationassociated with a well in which the communicator is deployed.
 15. Thecommunicator as claimed in claim 1 wherein the communicator includes arecordation playback configuration.
 16. The communicator as claimed inclaim 1 wherein the recordation playback configuration is a voicerecordation playback device.
 17. A system for setting a tool in adownhole environment comprising: a communicator configured to broadcasta signal; a downhole tool configured to receive the signal from thecommunicator and execute on an instruction conveyed by the signal, aradio wave inhibiting structure being interposed between thecommunicator and the downhole tool.
 18. The system as claimed in claim18 wherein the downhole tool further includes its own power source forexecuting on instructions received from the communicator.
 19. A methodfor communicating with a downhole tool comprising: delivering acommunicator to a position proximate a downhole tool; and emitting asignal from the communicator receivable by the downhole tool through aradio wave inhibiting structure without an opening therein for passageof radio waves.